Heavy oil spilled from the NAHOTOKA affected to environment in the Sea of Japan. Several heat and material transportation phenomena, such as coagulation with salts, evaporation of volatile substances to atmosphere and dissolution of soluble substances in the sea water, occurred during floating period in the sea. Furthermore, the dissolved hazardous substances and volatile substances effects on several plants. In this study, the composition and salts contents of the spilled oil from the NAHOTOKA was examined. The spilled oil contained 40〜50% of water and formed W/O emulsion. Most of sodium in the water phase transported to the oil phase. As the results of mixing experiment using C grade heavy oil and several water, the viscosity of the oil increased. The water drop in the (sea water)/(heavy oil) emulsion was smaller than those in (natural water)/(heavy oil) emulsion. The evaporation rate of volatile substances decreased by emulsion forming. The simple model of denature of floating oil on the sea was proposed. analytical results could represent the behavior of the volatile substance, Benzene and Naphthalene. Next, the uptake of volatile substances in the plant leaf was examined, It was estimated that the volatile substances was uptake through the stoma. The simple model of the environmental effects of the oil was proposed.